Add IMemoryToken and the HidlMemoryToken

The IMemoryToken is an interface which composes shared memory.
It provides a get() method, which returns an instance of hidl_memory
that always refer to the same memory.

The HidlMemoryToken is an implementation of the IMemoryToken.

Bug: 69640337
Test: hidl_test
Change-Id: Ida32a7971ba31e99f724c18159cf2e1f699b73b8

3 files changed, 69 insertions, 1 deletions

diff --git a/libhidlmemory/Android.bp b/libhidlmemory/Android.bp
index e854ab5..2135ef3 100644
--- a/libhidlmemory/Android.bp
+++ b/libhidlmemory/Android.bp
@@ -27,17 +27,20 @@ cc_library {
         "libcutils",
         "libhidlbase",
         "libhidltransport",
-        "android.hidl.memory@1.0"
+        "android.hidl.memory@1.0",
+        "android.hidl.memory.token@1.0",
     ],
     local_include_dirs: ["include"],
     export_include_dirs: ["include"],
 
     export_shared_lib_headers: [
         "android.hidl.memory@1.0",
+        "android.hidl.memory.token@1.0",
         "libhidlbase"
     ],
 
     srcs: [
+        "HidlMemoryToken.cpp",
         "mapping.cpp"
     ],
 
diff --git a/libhidlmemory/HidlMemoryToken.cpp b/libhidlmemory/HidlMemoryToken.cpp
new file mode 100644
index 0000000..3840183
--- /dev/null
+++ b/libhidlmemory/HidlMemoryToken.cpp
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <hidlmemory/HidlMemoryToken.h>
+
+namespace android {
+namespace hardware {
+
+HidlMemoryToken::HidlMemoryToken(sp<HidlMemory> memory) : mMemory(memory) {}
+
+Return<void> HidlMemoryToken::get(get_cb _hidl_cb) {
+    _hidl_cb(*mMemory);
+    return Void();
+}
+
+}  // namespace hardware
+}  // namespace android
diff --git a/libhidlmemory/include/hidlmemory/HidlMemoryToken.h b/libhidlmemory/include/hidlmemory/HidlMemoryToken.h
new file mode 100644
index 0000000..4020377
--- /dev/null
+++ b/libhidlmemory/include/hidlmemory/HidlMemoryToken.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef ANDROID_HARDWARE_HIDLMEMORYTOKEN_H
+#define ANDROID_HARDWARE_HIDLMEMORYTOKEN_H
+
+#include <android/hidl/memory/token/1.0/IMemoryToken.h>
+
+namespace android {
+namespace hardware {
+
+class HidlMemoryToken : public virtual ::android::hidl::memory::token::V1_0::IMemoryToken {
+   public:
+    Return<void> get(get_cb _hidl_cb) override;
+
+    HidlMemoryToken(sp<HidlMemory> memory);
+
+   protected:
+    sp<HidlMemory> mMemory;
+};
+
+}  // namespace hardware
+}  // namespace android
+#endif